Biodegradable embolic agents

Abstract

A flowable, biodegradable endovascular embolic composition effective for embolizing a vascular defect consisting essentially of: (a) a biocompatible, biodegradable polymer or polymeric material forming composition; (b) a biocompatible embolic solvent for the polymer or polymer forming composition capable of diffusion into mammalian tissue; (c) biocompatible magnetic particles responsive to a magnetic field; wherein: the polymer or polymeric forming material and solvent are present in the composition in amounts and relative proportions such that (1) the composition is deliverable to a vascular defect site and (2) upon delivery to the site, solidifies into an embolic mass; and the magnetic particles are present in the composition in an amount sufficient to enable the composition being deliverable to the vascular site by a magnetic field. Also disclosed are methods and articles of manufacture embodying the above-described composition.

1 . A flowable, biodegradable endovascular embolic composition effective for embolizing a vascular defect consisting essentially of: 
 (a) a biocompatible, biodegradable polymer or polymeric material forming composition;    (b) a biocompatible embolic solvent for said polymer or polymer forming composition;    (c) biocompatible magnetic particles responsive to a magnetic field;    wherein:    said polymer or polymeric forming material and solvent are present in said composition in amounts and relative proportions such that (1) said composition is deliverable to a vascular defect site and (2) upon delivery to said site, solidifies into an embolic mass; and    said magnetic particles are present in said composition in an amount sufficient to enable said composition being deliverable to said vascular site by a magnetic field.    
     
     
         2 . The composition of  claim 1  wherein said polymer or polymeric material forming composition is present in an amount of 2% to 50%, by weight for polymer.  
     
     
         3 . The composition of  claim 1  wherein said solvent is present in an amount of 5% to 60%, by weight.  
     
     
         4 . The composition of  claim 1  wherein said magnetic particles are present in an amount of 2% to 50%, by weight.  
     
     
         5 . The composition of  claim 1  wherein said polymer or polymeric material forming composition is polylactic acid, glycolic acid (PLGA), polycaprolactone or polyglutamate esters.  
     
     
         6 . The composition of  claim 1  wherein said solvent is DMSO, ethanol, ethyl lactate, acetone, N-methylpyrrolidone, ethylene glycol ethers (e.g., ethylene glycol dimethyl ether, or di-ethylene glycol dimethyl ether.  
     
     
         7 . The composition of  claim 1  wherein said magnetic particles are magnetite (Fe 3 O 4 ), maghemite, or iron sulfur minerals.  
     
     
         8 . The composition of  claim 1  wherein said magnetic particles are coated with a biocompatible surfactant.  
     
     
         9 . The composition of  claim 1  wherein said surfactant is a fatty acid or salt thereof.  
     
     
         10 . The composition of  claim 8  wherein said fatty acid is an 18 carbon atom acid.  
     
     
         11 . The composition of  claim 9  wherein said fatty acid is oleic acid.  
     
     
         12 . The composition of  claim 10  wherein said magnetic particles are coated with sodium oleate.  
     
     
         13 . The composition of  claim 1  also containing a radiopaque agent.  
     
     
         14 . The composition of  claim 1  wherein said radiopaque agent is barium sulfate, potassium iodide, an organic iodine containing molecule such as thyroxine.  
     
     
         15 . The composition also including a bioactive agent for sustained release from said embolic mass.  
     
     
         16 . The composition of  claim 12  wherein said bioactive agent is a drug or medicant.  
     
     
         17 . A method of treating a vascular defect comprising introducing the composition of  claim 1  into the vascular defect under the guidance of a magnetic field and positioning the composition in said vascular defect with said magnetic field under conditions wherein and until said composition solidifies into an embolic mass.  
     
     
         18 . An article of manufacture comprising the composition of  claim 1 .  
     
     
         19 . The article of manufacture of  claim 15  comprising packaging material and an embolic composition contained within said packaging material, wherein said embolic composition is effective for embolizing a vascular defect utilizing an applied magnetic field, and wherein said packaging material comprises a label which indicates that said embolic composition can be used for treating vascular defects and is deliverable to said vascular defect by an applied magnetic field, and wherein said embolic composition is that of  claim 1.